I got a pair of old Stancor push pull opt.  They list 10K center tapped input to 15/8/4/500 ohm output windings.   I have a question about what is possible to construct.  I have a 300b amp that I use for headphones with a Stax transformer adaptor.     The output impedance of 300b tube is...

I know I am probably a majority of one on these boards preferring SET amps with Stax transformers over Stax direct amps, however, once in a while somebody asks about transformer upgrades for the standard Stax boxes.   I was going to get a Woo Wee.  However, having heard Woo products, I was...

I have had some balance problems with my Stax 507 with the right channel being scratchy and low compared to the left.  I don't have an amplifier, but use one of the SRD 7 transformers with the pro and normal bias boards added.   I was wondering if the bias voltage was down, because the...

Re posted by suggestion from Headphone forum:   "I bought a pair of Lambda original low bias with a SRD 7 sd energizer. They look almost new, excellent condition and appearance, and work very well with a couple of tubed and SS amps through the energizer. I can't fault the sound, it seems...

I bought a pair of Lambda original low bias with a SRD 7 sd energizer. They look almost new, excellent condition and appearance, and work very well with a couple of tubed and SS amps through the energizer. I can't fault the sound, it seems very balanced and not the least bit thin, with full bass...